The present invention relates to a device for centering tools, such as saw blades, rotary cutters and the like which are circular and which have bores of different sizes, on processing machines such that they can be positioned about their center axes.
It is well known in the art that cutting tools such as industrial saw blades are provided with center bores (openings) having a variety of sizes. In order to sharpen such tools, it is necessary to position them on machines like grinders such that they are rotatable about their true center axes. This is commonly handled in shops that process (sharpen) such saw blades by providing, with each machine, a rather large quantity of bushings for selective trial in the saw blade to be finished. While this approach is commonly used, it is difficult and time consuming to find the right bushing to center each saw blade brought to the machine.
Some machinists have provided rather complex mechanisms comprising three jaws and a mechanism for moving the jaws radially outwardly and inwardly selectively to fit a blade. These mechanisms, however, are rather complex and are difficult to use for a wide range of bore sizes.
The device of the present invention is primarily concerned with centering saw blades having different bore sizes on a processing machine. According to other features, characteristics, embodiments and alternatives of the present invention which will become apparent as the description thereof proceeds below, the present invention provides a device for centering tools, such as saw blades, rotary cutters and the like which are circular and which have bores of different sizes, on processing machines such that they can be positioned about their center axes.
According to the illustrative embodiment of the disclosure, a centering device is provided for centering a circular cutting tool on a processing machine such as a saw blade grinder. The device comprises a mount adapted to be attached to the machine, a slide coupled to the mount and configured for movement relative to the mount, a first bearing mounted on the mount, and a second and a third bearing mounted on the slide for movement with the slide selectively toward and away from the first bearing. The slide and mount cooperate to support the tool and to present the tool to a processing element. The first, second and third bearings are engagable with the bore of the tool to cause the tool to be centered on the machine when the second and third bearings are moved from the first bearing securely pulling the tool bore against the first, second and third bearings, whereby the tool is then rotatable about its center axis. Each tooth of the saw blade can then be presented to a grinding wheel or other cutting device such that each tooth will be finished relative to the true center of the blade. An adjuster is also provided that is configured to move the slide selectively toward and away from the first bearing mounted on the mount.
A method of centering a tool on a machine is further disclosed. The method comprises the steps of providing a mount configured for coupling with a processing machine, providing a bearing on the mount, and providing a slide having a first row and a second row of holes. The slide is configured to move relative to the mount. The method further comprises the steps of positioning the tool on the mount and slide such that the bore engages the bearing and at least one hole from each row of holes is visible through the bore, placing a pin carrying a second bearing in an outermost visible hole of the first row, placing a pin carrying a third bearing in an outermost visible hole of the second row, and moving the slide relative to the mount such that the first, second, and third bearings engage and hold the bore of the tool.
Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.